IS 15758 (Part 4) :2007 ISO 15025:2000 W'mMmm ma-1-f ?-gwn?w w'F14 Tmmmlalma=m ii=hamta Indian Standard TEXTILES -- PROTECTIVE CLOTHING PART 4 TEST METHOD FOR LIMITED FLAME SPREAD Ics 13.340.10 @ BIS 2007 BUREAU MANAK August 2007 OF INDIAN STANDARDS ZAFAR MARG BHAVAN, 9 BAHADUR SHAH NEW DELHI 110002 Price Group 7 Chemical Methods of Test Sectional Committee, TX 05 NATIONAL FOREWORD This Indian Standard (Part 4) which is identical with ISO 15025 : 2000 `Protective clothing -- Protection against heat and flame -- Method of test for limited flame spread' issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on the recommendation of the Chemical Methods of Test Sectional Committee and approval of the ~ Textile Division Council. The conditioning temperature of 20 * 2°C as specified in International Standard is not suitable for tropical countries like India where the atmospheric temperature is.normally much higher than 20"C. It is almost impossible to maintain this temperature specially during summer when the atmospheric temperature rises even up to 50"C. In view of the above, IS 6359: 1971 `Method for conditioning of textiles' specifies a temperature of 27 * 2°C for conditioning of the test specimens for the tropical countries like India. This standard is being followed in testing of textiles and other products since decades. The text of ISO Standard has been approved as suitable for publication as an Indian Standard without deviations. Certain conventions are, however, not identical to those used in Indian Standards. Attention is particularly drawn to the following: a) Wherever the words `International Standard' or `European this standard, they should be read as `Indian Standard'. b) Standard' appear referring to Comma (,) has been used as a decimal marker, while in Indian Standards, practice is to use a point (.) as the decimal marker. the current In reporting the results of a test or analysis made in accordance with this standard, if the final value, observed or calculated, is to be rounded off, it shall be done in accordance with IS 2:1960 `Rules for rounding off numerical values (revised)'. IS 15758 (Part 4):2007 ISO 15025:2000 Indian Standard TEXTILES -- PROTECTIVE CLOTHING PART 4 TEST METHOD FOR LIMITED FLAME SPREAD 1 Scope This International Standard specifies a method for the measurement of limited flame spread properties of vertically oriented textile fabrics and industrial products in the form of single or multi-component fabrics (coated, quilted, multilayered, sandwich constructions, and similar combinations), when subjected to a small defined flame. This test method is not appropriate for materials that demonstrate extensive melting or shrinkage. 2 Terms and definitions For the purposes of this International Standard the following terms and definitions apply. 2.1 flame application time time for which the ignition flame is applied to the test specimen 2.2 after-flame time duration of flame length of time for which a material continues to flame, under the specified test conditions, after the ignition source has been removed NOTE zero. Afterflame time is measured to the nearest second and afterflame times of less than 1,0s should be recorded as 2.3 afterglow persistence of glowing combustion of a material under specified test conditions, after cessation of flaming or, if no flaming occurs, after removal of the ignition source NOTE Afterglow is a continuation of combustion with the evolution of heat and light but without flame. Some materials absorb heat during the flame application and continue to emit this absorbed heat after removal of the igniting flame. This glowing without combustion should not be recorded as afterglow. 2.4 afterglow time duration of afterglow time for which a material continues to afterglow, under specified test conditions after cessation of flaming or after removal of the ignition source NOTE zero. Afterglow time is measured to the nearest second and afterglow times of less than 1,0 s should be recorded as 2.5 char formation of a brittle residue when material is exposed to thermal energy 1 IS 15758 (Part 4):2007 ISO 15025:2000 2.6 debris material separating from the specimen during the test procedure and falling from the specimen without flaming 2.7 flaming debris material separating from the specimen during the test procedure and igniting the filter paper 2.8 hole (surface ignition of procedure A) break in the test specimen of at least 5 mm in any dimension continuous perimeter caused by melting, glowing or flaming NOTE 1 and having a If the hole is crossed by any material it is described as discontinuous. NOTE 2 This International Standard describes the reporting of holes in any separable layer of a multilayer specimen obtained during suface ignition testing [see 8.2.1.3 g) and 10 i)]. 3 Principle A defined flame from a specified burner is applied for 10 s to the surface or the bottom edge of textile specimens which are vertically oriented. Information is recorded on the spread of flame and afterglow, and on the formation of debris, flaming debris, or a hole, Afterflame time and afterglow time are recorded. NOTE 1 NOTE 2 Surface exposure tests may be performed on both sides of multilayer fabric assemblies. The bottom-edge ignition test may not offer acceptable reproducibility for testing some materials. 4 Health and safety of test operators Burning of materials may produce smoke and toxic gases which can affect the health of operators. Between tests, the atmosphere of the test location, which should be of adequate dimensions to avoid endangering the health of operators, should be cleared of smoke and fumes by an extractor fan or other means of ventilation (see 6.1). NOTE Smoke and fume emission may be subject to national regulations concerning atmospheric pollution control. 5 5.1 Reagents Gas, of commercial grade, either propane or butane or butane/propane mixtures. Commercial grade propane is preferred but other gases may be used and this fact recorded in the test report (see NOTE item b) in clause 10. 6 6.1 -- Apparatus Test apparatus -- General requirements Construction: consisting of material which shall not be adversely affected by the fumes and that is resistant to heat and flame. NOTE Some products of combustion are corrosive. 2 IS 15758 (Part 4):2007 ISO 15025:2000 -- Location: surrounded by a volume of air sufficient not to be affected by any reduction of oxygen concentration. Where an open-fronted cabinet is used for the test, provision shall be made to permit the specimen to be mounted at least 300 mm from any wall. 6.2 Mounting frame, constructed to a design capable of holding the test specimen holder (see 6.4 and Figure 1) and the gas burner (see 6.3 and Figure 2) in the specified relative orientation (see Figure 3). 6.3 Gas burner, as described in annex A (see Figure 2), capable of being moved from a standby position, where the tip of the burner is at least 75 mm from the test specimen, to either the horizontal or inclined operating position [see Figure 3a) and 3 b) respectively]. Dimensions in millimetres A tt 4 -- t q +1 0 m A +1 20 ( t Key 4 + -4 150 *1 4 -- 1 I I 1 Specimen support pin, (2* 0,5) mm diameter 2 3 4 Spacer stub, 2 mm diameter Mounting frame Specimen Figure 1 -- Test specimen holder 3 IS 15758 (Part 4):2007 ISO 15025:2000 Dimensions in millimetres 1 --#- 23645 N 0 o+1 ~ P' 0,1 A Lnn a) Gas burner arrangement t-% -i c) Flame stabilizer b) Gas jet Key 1 2 3 4 5 6 Fitted in during assembly Gas jet Choke tube Burner tube Flame stabilizer Notch Figure 2 -- Gas burner IS 15758 (Part 4) :2007 ISO 15025:2000 Dimensions in millimetres 0 4 to,os In JA4L -tTl!l\ ""Y* I k 40 d) Burner tube . v' I---J 9 Key 7 8 9 Gas-mixing zone Diffusion zone Air chamber 10 Outlet Figure 2 -- Gas burner (continued) 5 IS 15758 (Part 4):2007 ISO 15025:2000 Dimensions in millimetres D --3 --4 0 -- -- 0 W II ! 17 *1 II I `5 a) Face ignition k i / ./ ) /; 30" / b) Bottom. I N +1 0 * /5 --6 dge ignition 2 I q 1 2 I c) Horizontal stand-by position, horizontal reach adjustment Key . Burner Flame Mounting frame Specimen Mounting pin Nominal flame application point d) Verticai stand-by flame height 1 2 3 4 5 6 Figure 3 -- Flame position and adjustment 6 IS 15758 (Part 4):2007 ISO 15025:2000 6.4 Specimen holder, consisting of a rectangular metal frame having a specimen support pin at each corner of a rectangle of 190 mm length by 150 mm width (see Figure 1). 6.4.1 NOTE 6.4.2 8.1.2.1 Supporting pins, for the specimen having a (2 * 0,5) mm diameter and a length of (25* Longer pins may be needed for mounting thick or multilayer specimens. 1) mm. Spacer stub, for the purpose of locating the specimen in a plane at least '20 mm away from the frame (see and 8.1.3. 1), of 2 mm diameter and a length of at least 20 mm and positioned adjacent to each of the four pins. 6.5 Template, flat and rigid, made of a suitable material and of a size corresponding (200 mm x 160 mm). to the size of the specimen Holes approximately 4 mm in diameter shall be drilled in each corner of the template and positioned so that the distances between the centres of the holes correspond to the distances between the pins on the specimen holder (see Figure 1). The holes shall be located equidistant about the vertical centreline of the template. 6.6 -- Timing devices: One timing device to control and measure the flame application time, which can be set at 1 s intervals with an accuracy of 0,2s or better. Two timing devices reading to 0,2s or better are required to measure the afterflame time and/or afterglow time. These devices are started, preferably automatically, at the instant of test flame termination or removal, and are stopped manually. NOTE Alternatively, specified precision. 6.7 a video recording of the test can be made, provided that an on-screen timer is provided with the Filter paper, with the following characteristics: area specific mass: size: thickness: alpha cellulose content: 60 g/m2 to 100 g/m2 >(150mmx100 mm) -- -- -- -- 0,15 mm to 0,25 mm >95 ?40. 7 7.1 7.1.1 Sampling Sampling and sample preparation Number of specimens Using the template (6.5), mark two sets of three test specimens. Mark one set perpendicular to the other. For woven/knitted or similar materials, orient the lengthwise axis of the template in the machine and cross-machine direction. For surface ignition, where the two surfaces of the sample are visually dissimilar and preliminary testing indicates dissimilar flammability characteristics, each surface shall be tested by the use of a set of six specimens. An extra test specimen is required for the installation procedure (see 8.1.2 and 8.1.3) 7 IS 15758 ISO (Part 4):2007 15025:2000 7.1.2 Specimen-holder pin location marks Mark the position through which the pins on the specimen holder shall pass by means of the holes in the template (6.5). NOTE Where the fabric is of open construction (for instance scrim, gauze),, small pieces of adhesive tape may be affixed to the fabric at the pin sites and the position marked on the tape. 7.1.3 Test specimen size Cut out test specimens with dimensions of (200 t 2) mm x (160 ~ 2) mm. 7.1.4 Multi layer specimens When specimens are composed of multiple layers or materials that are not continuous over the entire specimen, position the material of the smaller dimension along the bottom edge of the specimen, in a manner consistent with its use in the protective clothing, including the manner of attachment and orientation. Specimens containing retroreflective tape or emblems EXAMPLE specimens where this specimen preparation procedure should be used. and lettering are typical examples of multiiayer 7.2 Conditioning atmosphere of the test sample Unless otherwise specified, test specimens shall be conditioned in an atmosphere having a temperature of (20 i 2) "C and a relative humidity of (65 f 5) % for at least 24 h. If testing is not carried out immediately after conditioning, place the conditioned test specimens in a sealed container. Testing of each specimen shall begin within 2 min of removing it from either the conditioning atmosphere or the sealed container. NOTE Care should be taken to avoid injury when mounting the specimens on the pins in the time specified. If necessary, the specimen may be mounted on the specimen holder (6.4) before removal from the conditioning atmosphere. 8 Procedure More practical information concerning the experimental aspects of this technique are given in annex B. NOTE 8.1 8.1.1 Installation of the test apparatus Test conditions The tests shall be performed in an atmosphere having a temperature between 10 "C and 30 `C, a relative humidity between 15 Y. and 807., and air movement less than 0,2 m/s at the commencement of the test of each specimen. Air movement shall not be influenced by mechanical devices operating during the test. NOTE 8.1.2 Draught shields may be required to maintain stability of the test flame. Procedure A -- Surface ignition 8.1.2.1 Mounting of the test specimen Place the test specimen (see 7.1.1 ) on the pins of the test specimen holder, making certain that the pins pass through the points marked off from the template and that the back of the specimen is at least 20 mm away from the rectangular metal frame of the test specimen holder. Fit the test specimen holder to the mounting frame with the specimen vertical. 8 k 15758 (Part 4) :2007 ISO 15025:2000 8.1.2.2 Operating position of the burner Position the burner (6.3) perpendicular to the surface of the test specimen so as to align the axis of the burner 20 mm above the line of the lower pins and with the vertical centreline of the face of the test specimen. Make sure that the tip of the burner stabilizer is (17 i 1) mm from the surface of the test specimen [see Figure 3 a)]. 8.1.2.3 Flame adjustment -- Horizontal reach Set the burner (6.3) in the vertical standby position. Light the burner and preheat it for at least 2 min. Move the burner into the horizontal standby position and adjust the horizontal reach of the flame to (25 *2) mm measured as the distance from the tip of the burner stabilizer to the extreme end of the yellow part of flame when viewed against a dark background [see Figure 3 c)]. The flame reach shall be checked before testing each set of six specimens. If the apparatus does not have a horizontal standby position, it shall be necessary to remove the test specimen before carrying out the flame adjustment. 8.1.2.4 Flame position Move the burner frdm the standby position to the horizontal operating position (see 8.1 .2.2). Confirm that the flame impinges on the test specimen in the correct location [see Figure 3 a)]. Test all six specimens within a total of 10 min from completion of the preheat procedure and flame adjustment (8.1 .2.3). 8.1.2.5 Debris If debris is observed during the installation test, the additional procedure of 8.1.4 shall be used for subsequent testing, to determine whether the debris is to be termed flaming debris. 8.1.3 8.1.3.1 Procedure Mounting B -- Bottom-edge ignition of the test specimen Place the test specimen (see 7.1 ) on the pins of the test specimen holder, making certain that the pins pass through the points marked off from the template and that the back of the specimen is at least 20 mm away from the rectangular metal frame of the test specimen holder. Fit the test specimen holder to the mounting frame with the specimen vertical. 8.1.3.2 Operating position of the burner Position the burner in front of, but below, the test specimen so as to lie in a plane passing through the vertical centreline of the test specimen and perpendicular to its surface with the longitudinal axis inclined upwards at a 30° angle to the vertical bottom edge of the test specimen. Make sure that the distance between the tip of the burner stabilizer and the bottom edge of the test specimen is (20* 1) mm, measured as shown in Figure 3 b). It may not be possible to obtain consistent results with fabrics which exhibit drape or sag. Surface ignition may be NOTE more appropriate for such fabrics. 8.1.3.3 Flame adjustment -- Vertical flame height Set the burner (6.3) in the vertical standby position. Light the burner and preheat it for at least 2 min. Adjust the flame height to (40*2) mm, measured as the distance from the tip of the burner stabilizer to the extreme end of the yellow part of flame when viewed against a dark background [see Figure 3 d)]. The flame height shall be checked before testing each set of six specimens. 9 IS 15758 (Part 4):2007 ISO 15025:2000 8.1.3.4 Flame position position (see 8.1 .3.2). Check that the bottom Move the burner from the standby position to the inclined operating edge of the test specimen bisects the flame [see Figure 3 b)]. 8.1.3.5 Debris If debris is observed during the installation test, the additional procedure of 8.1.4 shall be used for subsequent testing to determine whether the debris is to be termed flaming debris. 8.1.4 Detection of flaming debris (8.1 .2.5 or 8.1 .3.5) or in subsequent if the debris is to be classified as flaming testing, debris. the following If debris is observed in the installation procedure additional procedure shall be employed to determine A piece of filter paper (6.7), at least(150 x 100) mm shall be placed on a horizontal solid surface (50 f 5) mm below the bottom edge of the specimen with the centre of the filter paper directly below the centreline of the specimen. NOTE If the burner mechanism touches the filter paper when using bottom-edge the mounting plate and in each piece of filter paper used. ignition, a suitable slot should be cut in 8.2 8.2.1 8.2.1.1 Test Surface ignition Set up the apparatus as described in 8.1.2. materials, record 8.2.1.2 Position test specimen on the specimen holder (see 8.1 .2.1). For woven/knitted whether the machine or cross machine direction is vertical. 8.2.1.3 Apply the test flame for 10s and observe and record: a) b) c) whether any flaming reaches the upper edge or either vertical edge of the test specimen; afterfiame time; whether afterglow spreads beyond the flame spread area (usually the carbonized area; afterglow time; area) into the undamaged d) e) f) g) the occurrence of debris; whether debris ignites the filter paper (flaming debris), if applicable; whether a hole develops, and in which layer(s) for a multilayer specimen. When testing multilayer specimens, a hole formation should be reported in each separable layer. NOTE Repeat 8.2.1.2 and 8.2.1.3 on the remaining 8.2.1.4 specimens exposed towards the flame. 8.2.2 8.2.2.1 five test specimens, with the same surface of all Bottom-edge ignition Set up the apparatus as described in 8.1.3. 10 IS 15758 (Part 4):2007 ISO 15025: 2000 Position the first of a set of six fresh test specimens on the specimen 8.2.2.2 materials, record whether the machine or cross machine direction is vertical. holder. For woverdknitted Apply the test flame for 10s and observe and record behaviour as listed in 8.2.1.3, with the exception 8.2.2.3 of g) which is not applicable to bottom-edge ignition. When elected, measure char length using the procedure in annex C. NOTE The measurement of char length is optional. Some laboratories have reported that when using the bottom-edge ignition test it can be difficult to obtain consistent interlaboratory results for the measurement of the char length. 8.2.2.4 Repeat 8.2.2.2 and 8.2.2.3 specimens exposed towards the flame. on the remaining five test specimens, with the same surface of all q 9 Precision occurs. They These methods are used to determine whether or not flame spread to the edge of the specimen consistently detect two groups of fabrics: -- -- fabrics which give little or no afterflame and fabrics which burn completely. However, there are some intermediate fabrics which can demonstrate more extensive, but not complete, flame spread under specific circumstances, These intermediate fabrics can give widely scattered results from one specimen to another and may give different results with different test procedures, for instance surface or bottomedge ignition, and in different laboratories. An interlaboratory trial with eleven fabrics in six laboratories was carried out in 1990. Using surface ignition, ten of the fabrics tested gave zero or very short afterflame times (< 3s) and no afterglow. The remaining fabric consistently gave long but variable (from 8s to 17s) afterflame times without burning to the edge. Using bottomedge ignition only eight of the fabrics gave consistent, low afterflame times (< 2 s). The remaining three fabrics gave longer afterflame times, which varied considerably from one specimen to another, but only in some laboratories. On the fabrics included in this trial, the face ignition test (procedure A) gave consistent results whilst the bottomedge ignition test (procedure B) detected inconsistent intermediate behaviour on some fabrics in some laboratories only. 10 Test report The test report shall include the following information: a) a statement that the test was carried out in accordance with this International details of any deviation from it; the type of gas used; the date of test; the ambient conditions of temperature 8.1.1); and relative humidity in the area in which the test is carried out (see Standard, i.e. ISO 15025, and b) c) d) e) f) the technique used to attach fabrics which cannot be supported on pins (see 7.1.2); an identification of the fabric tested including details of any pretreatment, for instance a cleansing procedure; 11 IS 15758 (Part 4) :2007 ISO 15025:2000 g) the type of surface exposed towards the flame and the type of ignition used, i.e. surface or bottom-edge ignition; h) for each test specification; specimen the information itemized in 8.2.1.3 as required by the appropriate performance i) an indication of the layers developing holes during the surface ignition test as required in 8.2.1.3 for multilayer specimens. 12 IS 15758 (Part 4):2007 ISO 15025:2000 Annex A (normative) Description and construction of the burner A.1 Description The burnerl) provides a flame of suitable dimensions, the length of which can be adjusted from 10 mm to 60 mm. A.2 Construction The construction of the burner is shown in Figure 2 a). The burner consists of three parts: A.2.1 Gas jet The orifice diameter of the gas jet [see Figure 2 b)] shall be (0,19+ 0,02) mm. The orifice shall be drilled and after drilling, all burrs shall be removed from both ends of the drilled hole without rounding the corners. A.2.2 Burner tube The burner tube [see Figure 2 d)] consists of four zones: a) b) c) d) air chamber; gas-mixing zone; diffusion zone; gas outlet. Within the air chamber, the burner tube has four air holes 4 mm diameter for air inlet. The forward edge of the air holes is approximately level with the tip of the jet. The diffusion zone is of conical shape and has the dimensions indicated in Figure 2 d). The burner has a bore of 1,7 mm internal diameter and an outlet of 3,0 mm interna! diameter. A.2.3 Flame stabilizer The flame stabilizer is given in detail in Figure 2 c). 1) Details of the availability of the specified burner may obtained from the secretariat of lsoflc D.C. 20036-3954, 38/SC 19, American Textile USA. Manufacturers Institute, 1130 Connecticut Ave., NW, Suite 1200, Washington 13 IS 15758 (Part 4):2007 ISO 15025:2000 Annex B (informative) Experimental techniques The quality of the experimental techniques required will depend to a significant extent on the design of the equipment used. For example, the poorer the automation of the equipment, the greater the need will be for a more skilled operator to perform the test in order to obtain high precision. Some practical points of a general nature are as follows: a) For reasons of safety, the test equipment should be remote from the gas cylinder which can be located outside the building. In this case, a manually operated shut-off valve should be installed inside the room-housing of the test apparatus where the piping enters. On each occasion the equipment is used, time should be allowed for pure gas to reach the burner jet and provide a steady flame, The equipment should be installed and used in a manner to prevent shouldering particles, which may be carried away by hot gases or fall from the specimen, from coming to rest on combustible materials. Protective clothing, fire extinguishers and alarm signals should be available to the operator. b) c) It is important to keep the apparatus clean to maintain safety. Some unfinished fabrics, such as single knit-jersey knitted fabrics, are liable to curl. This tendency may be reduced by subsequent processing. It is desirable to test this type of fabric in its finished state. Residual material adhering to the pins after testing may be removed by scraping with a wire brush. Any shouldering material shall be extinguished before placing it with other waste in a non-combustible container. Preliminary tests should be undertaken to establish if one surface of the fabric under examination is likely to produce different flammability behaviour from the other. If they are different, the worst or both surfaces should be tested. d) e) 14 IS 15758 (Part 4):2007 ISO 15025:2000 Annex C (normative) Measurement of char length The char length shall be the distance from the end of the specimen when it is exposed to the flame, to the end of a tear (made lengthwise) of the specimen through the centre of the charred area determined as follows: The test specimen shall be folded lengthwise and creased by hand along a line through the highest peak of the charred area. A hook, made of steel wire, using a 76 mm length of wire and bent 13 mm from one end to form a 4Y' hook, shall be inserted into the specimen (or a hole of 6 mm diameter or less pinched out for the hook) at one side of the charred area 6 mm from the adjacent outside edge and 60 mm from the lower end weight of sufficient mass is required such that the mass of the weight and hook together shall equal the total tearing load required. A tearing force shall be applied gently to the test specimen by grasping the corner of the specimen at the opposite edge of the char from the load, and raising the specimen and weight clear of the supporting surface. The end of the tear shall be marked on the edge and the char length measurement made along the undamaged edge. The specific load applicable to the mass of the test specimen is given in Table C. 1 Table C.1 Mass of test specimen material before any fire retardant or coating glmz 50 to 200 Over 200 to 500 Over 500 to 800 Over 800 I Total tearing load for determining the char length kg 0,1 0,2 0,3 0,45 15 IS 15758 (Part 4):2007 ISO 15025:2000 Bibliography [1] 1S06940, Textile fabrics-- Burning behaviour -- Determination specimens. ISO 6941, Texti/e fabrics -- Burning behaviour -- Measurement oriented specimens. of ease of ignition of vertica//y oriented [2] of flame spread propeflies of vertically 16 Bureau of Indian Standards BIS is a statutory institution established under the Bureau of /rKIkm Standards Act, 1986 to promote harmonious development of the activities of standardization, marking and quality certification of goods a;ld attending to connected matters in the country. Copyright BIS has the copyright of all its publications. 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